a) The pyramid shape of the Swiss population in 2050 will have something around 37% of the population not-working, being either children or retirees. This means 37% of the material production of every working person, at the very minimum, will go to sustaining non-working persons. Basically, two persons produce the goods and services consumed by three people. A minimum wealth transfer of this size is hard for a working population to keep.
Notice that it's indifferent how those 37% are distributed from working to non-working. Whether in the form of private savings, or of State-managed retirement, or a mix, or whatever, those are all just so many manners to spread what a country concretely makes between its population. How imaginary numbers in this or that database are organized doesn't change the baseline reality, all those numbers say is that this person has a claim to this percentage of the total available at that moment in time.
b) The reduction in housing and other prices will be offset by the much higher consumption of goods and services from non-working people.
c) About crimes, maybe. The statistics aren't clear on that.
d) Whether they want it or not is indifferent. Since their population will continue declining, with the rate of non-working retirees consuming a higher and higher percentage of everything that's produced leaving less and less for the working population, the economy will slowly but constantly convert Switzerland into a third world country. Once it's weak enough, populations with high birth rates will take over the more and more empty territory.
Right now (this may change), high birth populations are Sub-Saharan Africans, Ultra-Orthodox Jews, the Amish and "quiver" Evangelical Chuches in the US, and a few other orthodox groups in the Middle East. If things proceed as they are, these are the groups that will inherit Earth, including all of Europe and North America.
That's neither good nor bad, it just is.
e) Racism is a cultural invention as any other culture. It was invented in the 18th century, is still going on, and as any other cultural thing, will eventually die as every culture eventually does.
In regard to success or failure of a population, a racist culture held by its members may improve or reduce survival rates. If the racist population is big enough and has other traits that promote birth rates, it will grow. If its small, it will shrink due to lack of enough families and eventually die off. Supposing it grows, depending on the genetic configuration of that population, it may become weak toward illnesses that more genetically diverse populations would develop natural resistance to, and die off due to a plague.
The way things are, Switzerland seems poised to have a combination of low birth rates, low genetic variation, and racism, which all put together prevents them from fixing their decline. That will merely accelerate their extinction, and that of their culture with them.